Short-wavelength instability and transition to chaos in distributed systems with additional symmetry

A review is presented of the theory of pattern formation in extended, dissipative, highly nonequilibrium systems. Emphasis is placed on systems which, in addition to spatial translations and rotations, have additional continuous symmetry group(s). It is shown that the additional symmetry destabilizes dramatically the ground state of the system thus causing it to make a direct transition from a spatially uniform to a turbulent state in an analogous fashion to the second-order phase transition in quasi-equilibrium systems. Apart from the theoretical analysis, a discussion of experimental data is given.